JP2003124773A - Chip type piezoelectric resonance component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chip type piezoelectric resonance component in which it is difficult to cause the fluctuation and failure of a characteristic due to the climbing of molten solder when mounted and which is excellent in reliability of electric connection and has a relative simple structure. SOLUTION: In this chip type piezoelectric resonance component 1 having a laminate 2 with first and second sealing substrates 4 and 5 laminated over and under an energy confining type piezo-resonator 3, first and second connection conductors 11 and 12 are formed on edge faces 2a and 2b of the laminate 2 connected electrically to first and second extraction electrodes of the piezo- resonator 3, the connection conductors 11 and 12 are formed so as to reach the bottom face, and first and second electrodes 8 and 9 with solder attached on lateral sides of the laminate when mounted are connected to the first and second connection conductors 11 and 12 in a face contactable way.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip-type piezoelectric resonance component such as a laminated piezoelectric oscillator, and more particularly to an energy trap type piezoelectric vibrating portion formed inside, Relates to a chip type piezoelectric resonance component having a plurality of external electrodes to be soldered when mounted on a printed circuit board or the like.

[0002]

2. Description of the Related Art Conventionally, various surface mount type electronic components having a structure in which a sealing substrate is laminated on and under an energy trapping type piezoelectric resonator have been proposed.

For example, Japanese Patent Laid-Open No. 2001-53573 discloses a piezoelectric resonance component shown in an exploded perspective view in FIG. In this piezoelectric resonance component 101, first and second sealing structures 103 and 104 are laminated on and under an energy trap type piezoelectric resonator 102 to form a laminated body. The first to third external electrodes 10 are provided on the side surfaces of the laminated body.
5-107 are formed. On the other hand, on the surface different from the side surface on the side where the external electrodes 105 to 107 are formed of this laminated body, that is, on the pair of end surfaces, the connection electrodes 108 and 10 are formed.
9 is formed. The connection electrodes 108 and 109 are electrically connected to the extraction electrodes 110a and 111a connected to the vibrating electrodes 110 and 111 of the piezoelectric resonator 102, respectively.

On the other hand, the first and second external electrodes 105, 10
6 is a vibrating electrode 1 via the connection electrodes 108 and 109.
It is electrically connected to 10, 111. In the configuration described in this prior art, the external electrodes 105, 1 are not used when soldering.
The part on the side surface of the laminate of No. 06 is used. On the other hand, the connection electrodes 108 and 109 are formed on the end faces of the stacked body.
Therefore, it is difficult for the molten solder to flow up through the connection electrodes 108 and 109, so that the extraction electrode 110 of the piezoelectric resonator 102 can be prevented.
It is said that molten solder can be prevented from entering the inside of the laminate from a and 111a.

[0005]

However, as shown in FIG. 9, for example, the external electrode 106 is formed only on the side surface 112a of the base substrate 112 which constitutes the lower portion of the second sealing structure 104. Instead, it is formed so as to reach the end surface 112b as well, and is electrically connected to the connection electrode 109 at the end surface 112b. Like the external electrode 106, the connection electrode 109 is also formed of a metal having excellent conductivity, and thus has good solder wettability. Therefore, when the molten solder is applied to the portion located on the side surface 112 a side of the external electrode 106, the molten solder may rise not only on the external electrode 106 but also on the connection electrode 109.

On the other hand, the base substrate 1 in which the connection electrodes 108 and 109 constitute the lower portion of the second sealing structure 104.
Connection outside 12 is also conceivable. However, in that case, the external electrodes 105 and 106 are connected to the connection electrode 10.
The external electrode extension for connecting to 8 and 109 must be formed, and the structure of the second sealing structure 104 must be complicated.

In the above prior art, the external electrode 106 is used.
From the bottom surface 112 d of the base substrate 112 to the side surface 112.
a, 112c to the upper surface 112e, the end surface 112b, the bottom surface 112d, and the side surfaces 112a, 112c.
And the upper surface 112e, but formed so as not to reach the inside of the end surface 112b. On the other hand, the connection electrode 109 is partially formed on the end surface of the stacked body, and the connection electrode 109 and the external electrode are formed. A structure is also shown in which the connection with 106 is made at the end face of the stack. In this case, the connection electrode must be partially formed on the end face,
Therefore, highly accurate positioning is required when forming the connection electrodes. In addition, the electrical connection between the external electrode and the connection electrode is achieved by the contact between the edge of the external electrode formed on the upper surface of the base substrate 112 and the connection electrode 109, that is, in line contact. Since they are electrically connected, there is a problem that the reliability of the electrical connection is poor.

The object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to connect the external electrode to be a soldering portion and the connection electrode connected to the lead electrode of the piezoelectric resonator on the outer surface of the laminate. In addition, it has excellent reliability of electrical connection between the connection electrode and the external electrode, and can suppress rising of molten solder at the connection electrode.
An object is to provide a chip type piezoelectric resonance component having a relatively simple structure.

[0009]

According to a broad aspect of the present invention, a piezoelectric substrate and first and second piezoelectric layers formed respectively on an upper surface and a lower surface of the piezoelectric substrate so as to face each other via the piezoelectric substrate.
Energy confinement type piezoelectric resonator having the vibrating electrode and the first and second extraction electrodes connected to the first and second vibrating electrodes and provided so as to reach the outer peripheral edge of the piezoelectric substrate. And a first sealing substrate laminated on the upper surface of the piezoelectric resonator while securing a space for preventing the vibration of the piezoelectric resonator, and a space for not disturbing the vibration of the piezoelectric resonator. Also, the second sealing substrate laminated on the lower surface of the piezoelectric resonator and the side surface or the end surface of the laminated body composed of the piezoelectric resonator and the first and second sealing substrates reach the lower surface. First and second external electrodes that are formed and soldered when mounted, and the first and second external electrodes so as to extend from the side surface or end surface of the laminate to the lower surface. It is formed separately from the electrodes, and on the side surface or end surface of the laminated body. And are electrically connected to the first and second extraction electrodes, respectively, and are superposed on the lower surface of the laminated body to the first and second external electrodes, respectively, and are connected in a surface contact manner. A chip-type piezoelectric resonance component is provided that includes a second connection conductor.

In a particular aspect of the present invention, the first and second
The outer electrode and the first and second connection conductors are formed on different surfaces of the side surface and the end surface of the laminated body. In this case, since the first and second connection conductors are formed on the different surfaces of the first and second external electrodes and the laminated body, the rising of the molten solder onto the connection conductor is further ensured. Can be suppressed.

In still another specific aspect of the present invention, the first and second external electrodes are electrically connected to the first and second extraction electrodes on a side surface or an end surface of the laminated body, respectively. . In this case, the first and second extraction electrodes are
Since it is electrically connected not only to the first and second connection conductors but also to the first and second external electrodes, the electrical connection between the extraction electrode of the piezoelectric resonator and the external electrode Reliability of the dynamic connection can be further improved.

In still another specific aspect of the present invention, the first and second connection conductors are made of a conductive resin, and therefore the solder wettability of the first and second connection conductors is low, so that the first and second connection conductors have low solder wettability. It is possible to reliably prevent the solder from rising onto the second connecting conductor.

In still another specific aspect of the present invention, the first and second connection conductors are laminated on the first conductor layer and outside the first conductor layer, and the first conductor layer is formed. The solder wettability suppressing layer is made of a material having a lower solder wettability than that of the first embodiment, and therefore, the rising of the outer surfaces of the first and second connection conductors is more effectively prevented. Preferably, the conductor layer is made of a metal having a relatively high conductivity, while the solder wettability suppressing layer is made of a resin or a metal having a relatively low conductivity.

In another particular aspect of the present invention, the first,
A recess is formed in the laminated body at a portion where the second connection conductor reaches the lower surface of the laminated body, and the first and second connection conductors are inserted in the recess. In this case, the first and second connecting conductors and the first and second external electrodes are brought into surface contact with each other in the concave portion, thereby increasing the thickness of the laminated body without increasing the thickness of the laminated body. The connection conductor and the first and second external electrodes can be electrically connected to each other.

Further, the first and second connection conductors may be formed so as to reach the upper surface of the laminated body. In this case, a recess may be formed in a portion where the first and second connection conductors reach on the upper surface of the laminate, and when the connection conductor is in the recess, the thickness of the laminate is increased. It is possible to improve the adhesion between the connection conductor and the laminated body without the need.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in more detail by describing specific embodiments of the present invention with reference to the drawings.

1 (a) and 1 (b) are a perspective view and a bottom view showing the appearance of a chip type piezoelectric resonance component according to the first embodiment of the present invention. The chip-type piezoelectric resonance component 1 has a laminated body 2. The laminated body 2 has a structure in which first and second sealing substrates 4 and 5 are laminated above and below a plate-shaped energy trap type piezoelectric resonator 3 with adhesive layers 6 and 7 interposed therebetween. On the outer surface of the laminated body 2, the first to third external electrodes 8 to 10 and the first and second connection conductors 11 and 12 are formed. First
The third external electrodes 8 to 10 are formed so as to reach the entire width on the bottom surface of the laminated body 2 and reach the upper surface of the laminated body 2 via both side surfaces. Figure 1 (b)
In, the first to third external electrodes 8 to 10 are shown with hatching.

The first and second external electrodes 8 and 9 are formed so that their side edges are along the end faces 2a and 2b of the laminate 2. The third external electrode 10 is arranged between the first and second external electrodes 8 and 9.

On the other hand, the connection conductors 11 and 12 are formed substantially at the centers of the end faces 2a and 2b of the laminated body 2, respectively. The connection conductors 11 and 12 extend in the vertical direction on the end surface of the laminated body 2, and are formed so that one end thereof reaches the upper surface and the other end thereof reaches the lower surface.

As shown in FIG. 3, the piezoelectric resonator 3 has a rectangular plate-shaped piezoelectric substrate 13. The piezoelectric substrate 13 is made of piezoelectric ceramics and is polarized in the thickness direction.
A vibrating electrode 14 is formed at the center of the upper surface of the piezoelectric substrate 13. A second vibrating electrode 15 is formed on the lower surface of the piezoelectric substrate 13. The second vibrating electrode 15 is formed so as to face the first vibrating electrode 14 via the piezoelectric substrate 13. The first and second extraction electrodes 16 and 17 are formed so as to be connected to the first and second vibrating electrodes 14 and 15. The extraction electrode 16 is an end surface 13 a of the piezoelectric substrate 13.
Is formed so as to reach the edge formed by the upper surface 13c. The second extraction electrode 17 is provided on the lower surface 13d of the piezoelectric substrate 13.
It is formed so as to reach the end edge formed by the end surface 13b.

As shown in FIG. 2, the adhesive layer 6,
7 has a rectangular frame shape. The openings 6a and 7a of the adhesive layers 6 and 7 form a space for not disturbing the vibration of the vibrating portion of the energy trap type piezoelectric resonator 3.

The lower surface 5a of the second sealing substrate 5 has an end surface 5
First recesses 5e and 5f are formed so as to open toward c and 5d. (See FIG. 1B) In FIG. 2, only the recess 5f is shown.

The first and second connecting conductors 11 and 12 enter the recesses 5e and 5f on the lower surface of the laminated body 2, that is, the lower surface of the second sealing substrate 5. Further, as shown in FIG. 4, the first extraction electrode 16 of the piezoelectric resonator 3 is electrically connected to the above-mentioned connection conductor 11 on the end face 2 a of the laminated body 2. Further, on the lower surface of the laminated body 2, the first external electrode 8 is formed so as to reach the inside of the recess 5e, and the first external electrode 8 is formed inside the recess 5e.
The connection conductors 11 overlap each other. Therefore, the first external electrode 8 is in surface contact with the first connection conductor 11 and is electrically connected thereto. Although not shown in FIG. 4, the second external electrode 9 is also in surface contact with the second connection conductor 12 in the same manner.

In the chip type piezoelectric resonance component 1 of this embodiment,
When mounted on a printed circuit board or the like, solder is applied to the side surface of the laminated body 2 of the first to third external electrodes 8 to 10. On the other hand, the connection conductors 11 and 12 connected to the extraction electrodes 16 and 17 are formed on the end surfaces 2 a and 2 b of the laminated body 2. That is, the connection conductor 1 is separated from the surface of the first and second external electrodes 8 and 9 to which the solder is applied, in other words, separated from the first and second external electrodes 8 and 9.
1, 12 are formed. Therefore, when soldering
It is difficult for the molten solder to rise up the connection conductors 11 and 12. Therefore, it is possible to prevent the molten solder from adhering to the extraction electrodes 16 and 17, and it is possible to obtain the chip-type piezoelectric resonance component 1 with less variation in electrical characteristics.

Moreover, the external electrodes 8 and 9 and the connection conductors 11 and
12 is connected in surface contact with the external electrodes 8,
The reliability of the electrical connection between 9 and the connecting conductors 11 and 12 is also improved. In addition, since the external electrodes 8 and 9 and the connecting conductors 11 and 12 are connected in surface contact with each other in the recesses 5e and 5f, the thickness of the chip-type piezoelectric resonance component 1 does not increase.

Further, when forming the connection conductors 11 and 12, a thin film forming method such as vapor deposition, plating or sputtering, or application of a conductive paste may be performed with reference to the recesses 5e and 5f. Therefore, it is not necessary to perform complicated positioning when forming the connection conductors 11 and 12.

FIG. 5 is a perspective view showing the external appearance of a modification of the chip-type piezoelectric resonance component according to the above embodiment. In the above embodiment, the first to third external electrodes 8 to 10 are formed so as to reach the upper surface through the side surfaces of the laminated body 2, but as shown in FIG. 5, the first to third external electrodes are formed. The electrodes 8 to 10 are the laminated body 2
May be formed so as to reach only the side surface portion of the second sealing substrate 5 on the side surface.

Further, as shown in FIG. 5, second recesses 4a and 4b opened toward the end faces 2a and 2b may be formed on the upper surface of the first sealing substrate 4. In this case, the first and second connection conductors 11 and 12 enter the recesses 4a and 4b. Therefore, in the chip-type piezoelectric resonance component 31 shown in FIG. 5, since no electrode is present on the upper surface of the laminated body 2, that is, the upper surface 4c of the first sealing substrate 4, it is possible to easily cope with three-dimensional high-density mounting. can do. Further, since no electrode is present on the upper surface of the laminated body 2, the chip-type piezoelectric resonance component 31 can be made thinner than the first embodiment. Since the other configurations are similar to those of the first embodiment, the description of the first embodiment will be incorporated.

FIG. 6 is a perspective view showing a chip type piezoelectric resonance component 41 according to another modification. In the chip-type piezoelectric resonance component 41, the first to third external electrodes 8 to 10 are the laminate 2
Is formed so as not to reach the upper surface of the. Connection conductor 1
Similarly to the first embodiment, 2 is surface-contacted with the second external electrode 9 on the lower surface of the laminated body 2. However, in the chip-type piezoelectric resonance component 41, the first concave portion has the laminated body 2 Is not formed on the lower surface of. The first connection conductor side is also configured similarly to the second connection induction side. Other configurations are similar to those of the first embodiment.

Also in the modification shown in FIG. 7, the connecting conductor 12 may be formed so as to extend to the intermediate height position of the end face 2b of the laminate 2. Although the connection conductor 11 is not shown, the connection conductor 11 is also formed so as to reach the intermediate height position of the end face 2 a, and does not reach the upper surface of the laminated body 2.

Thus, the connection conductor 1 according to the present invention
It is not always necessary to form 1 and 12 so as to reach the upper surface of the laminated body 2. Also, the first and second connection conductors 11, 1
2 was formed on the end faces 2a and 2b of the laminated body 2,
As in the modification shown in FIG. 8, the connection conductors 11 and 12 may be formed on the side surface of the laminated body 2. Here, the connection conductors 11 and 12 are formed so as to extend in the vertical direction on the side surface 2 d of the laminated body 2 and reach the upper surface and the lower surface of the laminated body 2.

On the other hand, the first to third external electrodes 8-10 are
It is formed so as to extend over the entire width of the lower surface of the laminated body 2 and to extend vertically in the side surface 2c. Also in this modification, the first and second external electrodes 8 and 9 are overlapped with the first and second connection conductors 11 and 12 on the lower surface of the laminated body 2 and are electrically connected in a surface contact manner. There is. Therefore, as in the first embodiment, the connection conductors 11 and 12 and the first and second conductors are connected.
The reliability of the electrical connection with the external electrodes 8 and 9 is improved.

When soldering, the solder is applied to the external electrodes 8 to 10 on the side surface 2c side.

As is apparent from the modification shown in FIG. 8, in the present invention, the connecting conductor does not necessarily have to be formed on the end face of the laminate, but may be formed on the side face of the laminate. Further, the first and second external electrodes 8 and 9 do not necessarily have to be formed on the same side surface of the laminated body 2,
It may be dispersed on different surfaces. Furthermore, the connecting conductor 1
As long as it is separated from the first and second external electrodes 11 and 12, 1 and 12 are preferably formed on a plurality of surfaces having different side surfaces and end surfaces, but they may be formed separated on the same surface. .

The connecting conductors 11 and 12 are made of a conductive resin in this embodiment. The conductive resin has lower solder wettability than metal. Therefore, also by this, rising of the solder in the connection conductors 11 and 12 can be suppressed.

The connection conductors 11 and 12 may be made of a material other than the conductive resin. For example, the connection conductor 11,
12 is a highly conductive metal such as Ag, Cu, Au, Ni,
A structure having a conductor layer made of Sn or the like and a solder wettability suppressing layer laminated on the outer surface of the conductor layer may be used. Examples of the material forming the solder wettability suppressing layer include a conductive or conductive resin, or a metal such as NiCu, NiCr, or Cr having a conductivity lower than that of the metal forming the conductor layer.

As described above, by laminating the solder wettability suppressing layer, it is possible to reliably prevent the solder from rising in the connecting conductors 11 and 12.

[0038]

In the chip type piezoelectric resonance component according to the present invention, the first and second extraction electrodes of the piezoelectric resonator are connected to the first and second connection conductors on the side surface or the end surface of the laminate, Further, the first and second connection conductors are respectively stacked on the lower surface of the laminated body and on the first and second external electrodes formed on the side surfaces or the end faces of the laminated body, and are connected in a surface contact manner. Therefore, since the connection conductor is connected to the extraction electrode, not to the first and second external electrodes to which solder is applied at the time of mounting, the molten solder is unlikely to adhere to the first and second connection conductors. Therefore, rising of the molten solder can be suppressed. In addition, the connection conductor is
Since the second external electrode is connected in a surface contact manner, the reliability of the electrical connection between the connection electrode and the connection conductor can be improved.

Therefore, according to the present invention, the chip-type piezoelectric element has a relatively simple structure, is less likely to cause characteristic variations and failures due to rising of molten solder during mounting, and is excellent in electrical connection reliability. It is possible to provide a resonance component.

[Brief description of drawings]

1A and 1B are a perspective view and a bottom view showing the appearance of a chip-type piezoelectric resonance component according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing respective members constituting a laminated body of the chip-type piezoelectric resonance component shown in FIG.

3 is a perspective view of a piezoelectric resonator used in the embodiment of FIG.

FIG. 4 is a partially cutaway cross-sectional view for explaining an electrically connecting portion between a first connecting conductor and a first external electrode in the chip type piezoelectric resonance component shown in FIG.

FIG. 5 is a perspective view showing the external appearance of a chip type piezoelectric resonance component according to a modification of the first embodiment.

6 is a perspective view showing a chip type piezoelectric resonance component according to another modification of the embodiment shown in FIG.

7 is a perspective view showing a chip type piezoelectric resonance component according to another modification of the embodiment shown in FIG.

8 is a perspective view showing a chip type piezoelectric resonance component according to another modification of the embodiment shown in FIG.

FIG. 9 is an exploded perspective view for explaining an example of a conventional chip type piezoelectric resonance component.

[Explanation of symbols]

1. Chip type piezoelectric resonance component 2 ... Laminated body 2a, 2b ... end faces 2c, 2d ... Sides 3 ... Piezoelectric resonator 4, 5 ... First and second sealing substrates 4a, 4b ... Second recess 5e, 5f ... 1st recessed part 6, 7 ... Adhesive layer 8-10 ... 1st-3rd external electrodes 11, 12 ... First and second connection conductors 13 ... Piezoelectric substrate 14, 15 ... First and second vibrating electrodes 16, 17 ... First and second extraction electrodes 31 ... Chip type piezoelectric resonance component

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] November 7, 2001 (2001.11.
7)

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 4

[Correction method] Change

[Correction content]

[Figure 4]

Claims (9)

[Claims] 1. A piezoelectric substrate, first and second vibrating electrodes respectively formed on an upper surface and a lower surface of the piezoelectric substrate so as to face each other via the piezoelectric substrate, and connected to the first and second vibrating electrodes. And an energy trapping type piezoelectric resonator having first and second extraction electrodes provided so as to reach the outer peripheral edge of the piezoelectric substrate, and a space for not disturbing the vibration of the piezoelectric resonator. A first sealing substrate that is stacked on the upper surface of the piezoelectric resonator while securing it, and a second sealing substrate that is stacked on the lower surface of the piezoelectric resonator while securing a space that does not hinder the vibration of the piezoelectric resonator. It is formed so as to reach from the side surface or the end surface to the lower surface of the laminated body composed of the encapsulation substrate and the piezoelectric resonator and the first and second encapsulation substrates, and is soldered when mounted. And a side surface of the laminated body, As it will reach the lower surface from the end face,
Further, it is formed so as to be separated from the first and second external electrodes, and is electrically connected to the first and second extraction electrodes respectively on the side surface or the end surface of the laminated body, and on the lower surface of the laminated body. A chip-type piezoelectric resonance component, comprising: first and second connection conductors, which are respectively superposed on the first and second external electrodes and connected in a surface contact manner. 2. The first and second external electrodes and the first and second connection conductors are formed on different surfaces of a side surface and an end surface of the laminate, respectively. Chip type piezoelectric resonance component. 3. The method according to claim 1, wherein the first and second external electrodes are electrically connected to the first and second extraction electrodes, respectively, on the side surface or the end surface of the laminated body. Chip type piezoelectric resonance component. 4. The chip type piezoelectric resonance component according to claim 1, wherein the first and second connection conductors are made of a conductive resin. 5. The first and second connection conductors are laminated on a first conductor layer and outside the first conductor layer, and have lower solder wettability than the first conductor layer. The chip-type piezoelectric resonance component according to claim 1, further comprising a solder wettability suppressing layer made of a material. 6. The chip mold according to claim 5, wherein the conductor layer is made of a metal having a relatively high conductivity, and the solder wettability suppressing layer is made of a resin or a metal having a relatively low conductivity. Piezoelectric resonance component. 7. A recess is formed in the laminated body at a portion where the first and second connecting conductors reach the lower surface of the laminated body, and the first and second connecting conductors are inserted into the concave portion. The chip-type piezoelectric resonance component according to any one of claims 1 to 6. 8. The chip-type piezoelectric resonance component according to claim 1, wherein the first and second connection conductors are formed so as to reach the upper surface of the laminated body. 9. The chip-type piezoelectric resonance component according to claim 8, wherein a recess is formed in a portion of the upper surface of the laminated body where the connection conductor reaches, and the connection conductor is inserted in the recess.